Ventilation tubings for aircraft airconditioning already are known which comprise a silicone fabric bush, a polyimide foam insulating layer and a cover sheet of chlorosulfonated polyethylene elastomer, or tubings that comprise a silicone fabric bush, a glass fiber insulating layer and a polyvinyl fluoride cover sheet. Again ventilation tubings are known which comprise a bush made of a resin composite, a polyimide foam insulation and a chlorosulfonated polyethylene cover sheet.
The above products entail the drawback of high weight, for instance being 1,200 g for a 2 m long tubing which is 205 mm in diameter, that is, more than 7 kg for a standard length of 12 m built up from six end-to-end tubings.
Moreover, as regards the above tubings, the two of them which are fitted with polyimide foam insulation clad with chlorosulfonated polyethylene elastomer do not meet the requirements of the ABD0007 standard regarding resistance to fluids.
On the other hand, the present standard, namely ABD0031, which applies to fire resistance in aeronautics, shall be complemented by a more stringent standard whereby the fire resistance test shall be run using a radiating panel.
Besides the drawback of their weight, the above cited tubings preclude this expansion of the standards.